package com.example.demo.config;

import com.example.demo.filter.JwtAuthenticationTokenFilter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.authentication.AuthenticationManager;
import org.springframework.security.config.annotation.method.configuration.EnableGlobalMethodSecurity;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.config.http.SessionCreationPolicy;
import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
import org.springframework.security.crypto.password.PasswordEncoder;
import org.springframework.security.web.AuthenticationEntryPoint;
import org.springframework.security.web.access.AccessDeniedHandler;
import org.springframework.security.web.authentication.AuthenticationFailureHandler;
import org.springframework.security.web.authentication.UsernamePasswordAuthenticationFilter;

import javax.annotation.Resource;

@Configuration
@EnableGlobalMethodSecurity(prePostEnabled = true)   // 可以使用注解去指定访问对应的资源所需的权限
public class SecurityConfig extends WebSecurityConfigurerAdapter {

    @Autowired
    private JwtAuthenticationTokenFilter jwtAuthenticationTokenFilter;

    @Autowired
    private AuthenticationEntryPoint authenticationEntryPoint;

    @Autowired
    private AccessDeniedHandler accessDeniedHandler;

    @Bean
    public PasswordEncoder passwordEncoder() {
        return new BCryptPasswordEncoder();

    }

    /**
     * 配置spring security请求
     *
     * @param http
     * @throws Exception
     */
    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
                //关闭csrf
                .csrf().disable()
                //不通过Session获取SecurityContext
                .sessionManagement().sessionCreationPolicy(SessionCreationPolicy.STATELESS)
                .and()
                .authorizeRequests()
                // 对于登录接口 允许匿名访问
                .antMatchers("/user/login").anonymous()
                // 除上面外的所有请求全部需要鉴权认证
                .anyRequest().authenticated();

        // 添加过滤器
        http.addFilterBefore(jwtAuthenticationTokenFilter, UsernamePasswordAuthenticationFilter.class);

        // 添加异常处理
        http.exceptionHandling()
                .authenticationEntryPoint(authenticationEntryPoint)
                .accessDeniedHandler(accessDeniedHandler);

        // security 配置跨域
        http.cors();
    }

    /**
     * 权限认证器
     *
     * @return
     * @throws Exception
     */
    @Bean
    @Override
    public AuthenticationManager authenticationManagerBean() throws Exception {
        return super.authenticationManagerBean();
    }
}
